"It's not every day I just jump out of bed and say, 'Wow, this is a happy day,' but I know if I wake up and feel my head is heavy, that I'm not feeling so good, I know I can make it a good day anyway -- that's my choice.

"I can choose to be, 'Oh, tell everybody I'm not feeling so well,' or I can tell myself, 'No, I want to feel good and tell everybody I'm feeling good.' It's my choice. That's kind of a freedom."

Even scrolling through the complete list of Fredskov's marathons on her website is exhausting.

All of them were completed in Denmark, most around the town of Næstved. Unsurprisingly, Fredskov's very first marathon was her quickest, clocking in at four hours, 25 minutes and 30 seconds.

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She drank two liters of soda a day to keep her body infused with sugar, got through a pair of running shoes every 18 days, and maintained an average time of around five hours.

"There were lonely moments, because I was the only one doing this," she explained.

"Sometimes I just felt so tired and thought, 'Nobody knows what I'm feeling right now,' and that sometimes felt lonely.

"Also when people told me, 'You can do this, try that,' and I thought you don't know what you're talking about because I'm the only one who has tried to run a marathon and it's hard -- I'm tired!"

A glutton for punishment, Fredskov decided to run not one but two marathons on her 365th day, spending a total of 10 hours and 45 minutes pounding the roads.

"When I got to the finish line, I had no words," she said. "It was overwhelming, my head was empty. The only thing going through my mind was thank you for everything.

"I ran over the finish line and my kids and my husband were there ready to hug me, and Emilia and Victor they made a big sign saying, 'You are awesome mum!'

"I just started crying -- it was the best day of my life. I have a lot of those but it's going into history."

As you might have guessed, her marathon year isn't the limit of Fredskov's ambitions, and another assignment is already in the pipeline.

"My next challenge in the running shoes is completing five marathons in 48 hours," she reports.